started to implement #283

This commit is contained in:
Niels 2016-07-23 09:59:09 +02:00
parent ddfe86cc49
commit 75dbbc55cf
3 changed files with 260 additions and 113 deletions

View file

@ -3633,8 +3633,8 @@ class basic_json
/*!
@brief access specified object element with default value
Returns either a copy of an object's element at the specified key @a key or
a given default value if no element with key @a key exists.
Returns either a copy of an object's element at the specified key @a key
or a given default value if no element with key @a key exists.
The function is basically equivalent to executing
@code {.cpp}
@ -3706,13 +3706,60 @@ class basic_json
/*!
@brief overload for a default value of type const char*
@copydoc basic_json::value()
@copydoc basic_json::value(const typename object_t::key_type&, ValueType)
*/
string_t value(const typename object_t::key_type& key, const char* default_value) const
{
return value(key, string_t(default_value));
}
/*!
@brief access specified object element via JSON Pointer with default value
@param[in] ptr a JSON pointer to the element to access
@param[in] default_value the value to return if @a ptr found no value
@tparam ValueType type compatible to JSON values, for instance `int` for
JSON integer numbers, `bool` for JSON booleans, or `std::vector` types for
JSON arrays. Note the type of the expected value at @a key and the default
value @a default_value must be compatible.
@since version 2.0.2
*/
template <class ValueType, typename
std::enable_if<
std::is_convertible<basic_json_t, ValueType>::value
, int>::type = 0>
ValueType value(const json_pointer& ptr, ValueType default_value) const
{
// at only works for objects
if (is_object())
{
// if pointer resolves a value, return it or use default value
try
{
return ptr.get_checked(this);
}
catch (std::out_of_range&)
{
return default_value;
}
}
else
{
throw std::domain_error("cannot use value() with " + type_name());
}
}
/*!
@brief overload for a default value of type const char*
@copydoc basic_json::value(const json_pointer&, ValueType)
*/
string_t value(const json_pointer& ptr, const char* default_value) const
{
return value(ptr, string_t(default_value));
}
/*!
@brief access the first element

View file

@ -3633,8 +3633,8 @@ class basic_json
/*!
@brief access specified object element with default value
Returns either a copy of an object's element at the specified key @a key or
a given default value if no element with key @a key exists.
Returns either a copy of an object's element at the specified key @a key
or a given default value if no element with key @a key exists.
The function is basically equivalent to executing
@code {.cpp}
@ -3706,13 +3706,60 @@ class basic_json
/*!
@brief overload for a default value of type const char*
@copydoc basic_json::value()
@copydoc basic_json::value(const typename object_t::key_type&, ValueType)
*/
string_t value(const typename object_t::key_type& key, const char* default_value) const
{
return value(key, string_t(default_value));
}
/*!
@brief access specified object element via JSON Pointer with default value
@param[in] ptr a JSON pointer to the element to access
@param[in] default_value the value to return if @a ptr found no value
@tparam ValueType type compatible to JSON values, for instance `int` for
JSON integer numbers, `bool` for JSON booleans, or `std::vector` types for
JSON arrays. Note the type of the expected value at @a key and the default
value @a default_value must be compatible.
@since version 2.0.2
*/
template <class ValueType, typename
std::enable_if<
std::is_convertible<basic_json_t, ValueType>::value
, int>::type = 0>
ValueType value(const json_pointer& ptr, ValueType default_value) const
{
// at only works for objects
if (is_object())
{
// if pointer resolves a value, return it or use default value
try
{
return ptr.get_checked(this);
}
catch (std::out_of_range&)
{
return default_value;
}
}
else
{
throw std::domain_error("cannot use value() with " + type_name());
}
}
/*!
@brief overload for a default value of type const char*
@copydoc basic_json::value(const json_pointer&, ValueType)
*/
string_t value(const json_pointer& ptr, const char* default_value) const
{
return value(ptr, string_t(default_value));
}
/*!
@brief access the first element

View file

@ -3767,6 +3767,8 @@ TEST_CASE("element access")
}
SECTION("access specified element with default value")
{
SECTION("given a key")
{
SECTION("access existing value")
{
@ -3889,6 +3891,57 @@ TEST_CASE("element access")
}
}
SECTION("given a JSON pointer")
{
SECTION("access existing value")
{
CHECK(j.value("/integer"_json_pointer, 2) == 1);
CHECK(j.value("/integer"_json_pointer, 1.0) == Approx(1));
CHECK(j.value("/unsigned"_json_pointer, 2) == 1u);
CHECK(j.value("/unsigned"_json_pointer, 1.0) == Approx(1u));
CHECK(j.value("/null"_json_pointer, json(1)) == json());
CHECK(j.value("/boolean"_json_pointer, false) == true);
CHECK(j.value("/string"_json_pointer, "bar") == "hello world");
CHECK(j.value("/string"_json_pointer, std::string("bar")) == "hello world");
CHECK(j.value("/floating"_json_pointer, 12.34) == Approx(42.23));
CHECK(j.value("/floating"_json_pointer, 12) == 42);
CHECK(j.value("/object"_json_pointer, json({{"foo", "bar"}})) == json(json::object()));
CHECK(j.value("/array"_json_pointer, json({10, 100})) == json({1, 2, 3}));
CHECK(j_const.value("/integer"_json_pointer, 2) == 1);
CHECK(j_const.value("/integer"_json_pointer, 1.0) == Approx(1));
CHECK(j_const.value("/unsigned"_json_pointer, 2) == 1u);
CHECK(j_const.value("/unsigned"_json_pointer, 1.0) == Approx(1u));
CHECK(j_const.value("/boolean"_json_pointer, false) == true);
CHECK(j_const.value("/string"_json_pointer, "bar") == "hello world");
CHECK(j_const.value("/string"_json_pointer, std::string("bar")) == "hello world");
CHECK(j_const.value("/floating"_json_pointer, 12.34) == Approx(42.23));
CHECK(j_const.value("/floating"_json_pointer, 12) == 42);
CHECK(j_const.value("/object"_json_pointer, json({{"foo", "bar"}})) == json(json::object()));
CHECK(j_const.value("/array"_json_pointer, json({10, 100})) == json({1, 2, 3}));
}
SECTION("access non-existing value")
{
CHECK(j.value("/not/existing", 2) == 2);
CHECK(j.value("/not/existing", 2u) == 2u);
CHECK(j.value("/not/existing", false) == false);
CHECK(j.value("/not/existing", "bar") == "bar");
CHECK(j.value("/not/existing", 12.34) == Approx(12.34));
CHECK(j.value("/not/existing", json({{"foo", "bar"}})) == json({{"foo", "bar"}}));
CHECK(j.value("/not/existing", json({10, 100})) == json({10, 100}));
CHECK(j_const.value("/not/existing", 2) == 2);
CHECK(j_const.value("/not/existing", 2u) == 2u);
CHECK(j_const.value("/not/existing", false) == false);
CHECK(j_const.value("/not/existing", "bar") == "bar");
CHECK(j_const.value("/not/existing", 12.34) == Approx(12.34));
CHECK(j_const.value("/not/existing", json({{"foo", "bar"}})) == json({{"foo", "bar"}}));
CHECK(j_const.value("/not/existing", json({10, 100})) == json({10, 100}));
}
}
}
SECTION("front and back")
{
// "array" is the smallest key